In her second talk, Churchland outlines her group’s studies of the relationship between decision-making and action. She notes that in addition to methods to track neural activity, high-resolution videos of the decision-making process in mice provide valuable movement data. Using labeled calcium to visualize neural activity across the dorsal cortex, Churchland’s group finds that maps… Continue Reading
iBiology Podcasts
Anne Churchland Part 1: How Do Brains Decide?
How do brains make decisions? In this seminar, Dr. Anne Churchland tells us why understanding decision-making is important, and outlines common approaches to study decision-making in the lab using a variety of mammals. She describes findings that suggest accurate decision-making results from a combination of visual and auditory stimuli in both humans and rats, and… Continue Reading
Rebecca Christofferson Part 3: Characterizing Understudied Arboviruses: The Case of Orthobunyaviruses in Rwanda
Christofferson also works on characterizing understudied arboviruses like Bunyamwera, Batai, and Ngari, all of which are orthobunyaviruses. First, in the laboratory, her lab studied the growth of these Orthobunyaviruses in-vitro and investigated a mouse model to determine the cross-reactivity of these viruses. In addition, in collaboration with scientists in Rwanda, Christofferson investigated whether Bunyamwera, Batai… Continue Reading
Rebecca Christofferson Part 2: Math and Mosquitoes: Modeling to Understand Viral Processes Driving Emergence
In her second talk, Christofferson uses the Aedes aegypti-Zika system to explain how mosquito-life traits can be used to understand the process of vector competence. Zika is an arbovirus that is transmitted to humans via the Aedes aegypti mosquito. Christofferson measures how much time it takes for a mosquito to become infectious after its initial… Continue Reading
Rebecca Christofferson Part 1: Mosquito-Borne Arboviruses: How Environmental Changes Affect Disease Transmission
In this talk, Dr. Rebecca Christofferson provides an overview of arboviruses, arthropod-borne viruses, like dengue. Arthropods, such as mosquitoes, act as vectors to transmit diseases to vertebrates, including humans. Christofferson studies arthropod-virus-vertebrate interactions and how environmental factors affect disease transmission. For example, she explains how environmental factors, like changes in temperature and drought, affect the… Continue Reading
Howard Chang Part 3: LncRNA Function at the DNA Level: PVT1
In his Part 3, Chang reminds us that every lncRNA gene has its own set of DNA regulatory elements, such as enhancers and promoters. These regulatory elements can confer functionality to lncRNA genes. Chang shares the research story of a mysterious lncRNA known as PVT1, which is frequently co-amplified with the proto-oncogene MYC in human… Continue Reading
Howard Chang Part 2: LncRNA Function at the RNA Level: Xist
In his Part 2, Chang introduces long noncoding RNAs, or lncRNAs. As their name suggests, lncRNAs are not translated into proteins, and initially their functions were poorly understood. Chang’s group has developed technologies to better understand the function of lncRNAs. For example, his lab characterized the protein partners that interact with Xist, a canonical lncRNA… Continue Reading
Howard Chang Part 1: Epigenomic Technologies
In Part 1 of this series, Dr. Howard Chang introduces epigenomics, the study of DNA regulatory mechanisms that determine which genes are turned on or off in cells at specific times. The epigenome integrates signals from the environment to modify expression of the DNA blueprint inherited from an individual’s parents. Chang’s lab has pioneered techniques… Continue Reading
Eric Chow Part 2: Illumina NGS Sample Preparation
Chow discusses Illumina NGS Sample Preparation. He goes over DNA and RNA preparation, bead-based (Ampure or SPRI) cleanups, and sample quantification and quality control. Continue Reading
Eric Chow Part 3: Purifying DNA Samples with Magnetic Beads
Chow gives advice on purifying DNA samples using magnetic beads and on determining the quality of your nucleic acid sample using an Agilent Bioanalyzer. Continue Reading
Eric Chow Part 4: Checking Nucleic Acids with an Agilent BioAnalyzer
Chow gives advice on purifying DNA samples using magnetic beads and on determining the quality of your nucleic acid sample using an Agilent Bioanalyzer. Continue Reading
Eric Chow Part 1: Next Generation Sequencing
In the past decade there has been an amazing change in the efficiency of DNA sequencing. Using traditional Sanger sequencing, the human genome project took 20 years and cost $3 billion. Current next generation sequencing methods allow a human genome to be sequenced for $1000, in 48 hours! In this talk, Eric Chow explains the… Continue Reading
Malcolm Campbell: Introduction to the Scientific Teaching Series
Course Directors A. Malcolm Campbell, Kimberly Tanner, and Bill Wood talk about the reasons why we need to reform undergraduate biology education and why they got involved in the Scientific teaching Series project. Continue Reading
Katherine Thompson-Peer: Neuronal Regeneration After Dendrite Injury
Katherine Thompson-Peer examines neuronal regeneration, focusing on the ability of dendrites to regrow after injury. Continue Reading
Elly Tanaka Part 2: Signaling Molecules in Limb Regeneration
Tanaka expands on her work on signaling in axolotl limb regeneration. She explains how her lab used the technique of expression cloning to identify several factors required to trigger the cell migration and proliferation required for regeneration. Tanaka was also curious about what signals differentiate a wound from an amputation. It was known that regeneration… Continue Reading
Elly Tanaka Part 1: Axolotl Limb Regeneration
Among four limbed animals, salamanders are the champions of regeneration. They can regenerate an amputated leg or tail, as well as various internal organs. In her first talk, Elly Tanaka explains that axolotl limb regeneration is an excellent system to study the cellular and molecular mechanisms of limb regeneration in vertebrates. Tanaka and her colleagues… Continue Reading
Megan Sykes Part 3: Xenotransplantation
Sykes provides an overview of xenotransplantation, the use of organs or grafts from other (non-human) species. She outlines the challenges encountered with cross-species transplantation, and how scientist have been able to overcome these difficulties. Sykes and other laboratories are exploring the use of miniature pigs for xenotransplantations to humans. Sykes shows the outcome of xenotransplantations performed between different species… Continue Reading
Megan Sykes Part 1: Introduction to Transplantation
Dr. Megan Sykes provides an introduction to the field of organ transplantation and discusses the immunological responses associated with this procedure. Rejection is a major limitation to the success of transplantation. Sykes explains what causes rejection episodes in different types of transplantation, and outlines what we can do to prevent this from happening. Continue Reading
Megan Sykes Part 2: Taming and Tracking the Human Alloresponse
As Sykes explains, the Holy grail of transplantation is tolerance, the long-term graft acceptance without the long-term use of immunosuppressants. Sykes and collaborators developed a hematopoietic cell transplantation and mixed chimerism technique that proved to induce true tolerance in humans. They showed that transient mixed chimerism, the co-existence of donor and recipient hematopoietic elements, was… Continue Reading
James Spudich Part 2: A Brief History of Muscle Biology 1969-2017
Spudich describes the technological and experimental advances of the last ~50 years that have allowed researchers to understand muscle contraction in molecular detail. The development of an in vitro assay let Spudich and his colleagues determine which domain of the myosin molecule (which is very large) is necessary for movement. A laser trap assay allowed… Continue Reading
James Spudich Part 3: Ca 2+ Regulation of Muscle Contraction
Spudich recounts his first foray into muscle research as a postdoc in Hugh Huxley’s lab. He wanted to understand how Ca2+ regulated muscle contraction via the troponin/tropomyosin complex. Using electron micrographs and diffraction analysis to investigate where tropomyosin filaments lie along actin filaments, Spudich showed that tropomyosin filaments block the myosin-binding sites on actin. When… Continue Reading
James Spudich Part 4: Myosin Mutations and Hypertrophic Cardiomyopathy
Spudich focuses on current studies in his lab to understand how mutations in cardiac myosin cause human hypertrophic cardiomyopathy (HCM). This is a disease characterized by a hyper-contractile heart and is the most common cause of sudden cardiac arrest in people under 35 years old. Based on insight from a dream, Spudich realized that many… Continue Reading
James Spudich Part 1: A Brief History of Muscle Biology 1864-1969
Dr. Spudich begins his talks with a clear overview of muscle biology. Muscles are made of many cells and each cell contains many contractile units called sarcomeres. Sarcomeres are made of parallel filaments of two different proteins, actin and myosin. The filaments slide relative to each other and cause the sarcomere, and in turn the… Continue Reading
Geraldine Seydoux Part 2: How to Polarize the Cytoplasm
Seydoux explains how the PAR domains reorganize other proteins in the cytoplasm of the one-cell embryo and creates a body axis. MEX-5 is an RNA-binding protein that localizes to the anterior side of the embryo, forming a concentration gradient in the cytoplasm. Excitingly, her lab discovered that the MEX-5 gradient is caused entirely by the… Continue Reading